“Recently there’s been lots of little caterpillars crawling around everywhere,” says this reader from Austin, Texas. She is referring to the dark green worm-like creature photographed below, which sports a long body, and a bulbous, brown head.

“I have mainly seen them on the ground, but they are also tucked into the tall grass and weeds,” she continues. She thinks that they are “obviously the larvae of something bigger”, but of what she does not know, and that is what she wants our help with. Additionally, although she does not know what the caterpillars’ diet consists of, she guesses that they are eating the grass that they are in. “I just wonder if they are going to turn in to a pest as they mature.”

Firstly, we think our reader is correct in identifying these as caterpillars. The creature’s body shape and coloration indicates this.

Secondly, we want to point out that it is true that caterpillars can become more of a nuisance the larger they grow, as they are able to eat more the bigger they get. Hence, they do ‘become more of a pest’ as they mature in that sense. With that said, as they mature through their stages of life, going from caterpillar to pupa, and from pupa to butterfly/moth, they always become ‘less of a pest’, and more often than not, they are no longer pests once they mature past being a caterpillar.

Thirdly, we think that this is a fern caterpillar. Specifically, we think these might be Florida fern caterpillars, though this is but an educated guess. The Florida fern caterpillar can grow up to 1.5-inches in length and comes in various shades of green. Typically, they start as a bright green color and then will get darker as they mature.

Florida fern caterpillars are indeed pests, known for being able to cause significant damage to the type of plants they are named after. So, if our reader has any fern plants she would like to protect, then she might want to spray the leaves with some soapy water to make it harder for the caterpillars to climb the plants.

With all of that said, fern caterpillars are not harmful to humans or pets, so our reader needs not worry for her health. And if she has no ferns to worry about, then really does not have to do anything.

To conclude, we think that the dark green organism our reader found is a Florida fern caterpillar. We hope this article proves insightful, and we wish her the very best.

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